package org.apache.maven.model.profile.activation;

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

import java.io.File;

import org.apache.maven.model.Activation;
import org.apache.maven.model.ActivationFile;
import org.apache.maven.model.Profile;
import org.apache.maven.model.building.ModelProblemCollector;
import org.apache.maven.model.building.ModelProblem.Severity;
import org.apache.maven.model.building.ModelProblem.Version;
import org.apache.maven.model.building.ModelProblemCollectorRequest;
import org.apache.maven.model.path.PathTranslator;
import org.apache.maven.model.profile.ProfileActivationContext;
import org.codehaus.plexus.component.annotations.Component;
import org.codehaus.plexus.component.annotations.Requirement;
import org.codehaus.plexus.interpolation.AbstractValueSource;
import org.codehaus.plexus.interpolation.MapBasedValueSource;
import org.codehaus.plexus.interpolation.RegexBasedInterpolator;
import org.codehaus.plexus.util.StringUtils;

/**
 * Determines profile activation based on the existence/absence of some file.
 * 
 * @author Benjamin Bentmann
 * @see ActivationFile
 */
@Component(role = ProfileActivator.class,
    hint = "file")
public class FileProfileActivator implements ProfileActivator {

  @Requirement
  private PathTranslator pathTranslator;

  public FileProfileActivator setPathTranslator(PathTranslator pathTranslator) {
    this.pathTranslator = pathTranslator;
    return this;
  }

  public boolean isActive(Profile profile, ProfileActivationContext context, ModelProblemCollector problems) {
    Activation activation = profile.getActivation();

    if (activation == null) {
      return false;
    }

    ActivationFile file = activation.getFile();

    if (file == null) {
      return false;
    }

    String path;
    boolean missing;

    if (StringUtils.isNotEmpty(file.getExists())) {
      path = file.getExists();
      missing = false;
    } else if (StringUtils.isNotEmpty(file.getMissing())) {
      path = file.getMissing();
      missing = true;
    } else {
      return false;
    }

    RegexBasedInterpolator interpolator = new RegexBasedInterpolator();

    final File basedir = context.getProjectDirectory();

    if (basedir != null) {
      interpolator.addValueSource(new AbstractValueSource(false) {
        public Object getValue(String expression) {
          /*
           * NOTE: We intentionally only support ${basedir} and not ${project.basedir} as the latter
           * form would suggest that other project.* expressions can be used which is however beyond
           * the design.
           */
          if ("basedir".equals(expression)) {
            return basedir.getAbsolutePath();
          }
          return null;
        }
      });
    } else if (path.contains("${basedir}")) {
      return false;
    }

    interpolator.addValueSource(new MapBasedValueSource(context.getProjectProperties()));

    interpolator.addValueSource(new MapBasedValueSource(context.getUserProperties()));

    interpolator.addValueSource(new MapBasedValueSource(context.getSystemProperties()));

    try {
      path = interpolator.interpolate(path, "");
    } catch (Exception e) {
      problems.add(new ModelProblemCollectorRequest(Severity.ERROR, Version.BASE)
          .setMessage(
              "Failed to interpolate file location " + path + " for profile " + profile.getId() + ": " + e.getMessage())
          .setLocation(file.getLocation(missing ? "missing" : "exists")).setException(e));
      return false;
    }

    path = pathTranslator.alignToBaseDirectory(path, basedir);

    File f = new File(path);

    if (!f.isAbsolute()) {
      return false;
    }

    boolean fileExists = f.exists();

    return missing ? !fileExists : fileExists;
  }

}
